Our basic approach for deriving subdwarf distances is the same as the one used by [1]}, except that we replace the Hipparcos parallaxes by Gaia EDR3 ones. We start using the compilation of precise Johnson-Cousins UBVRI
photometry of nearby subdwarfs by [2]} and identify the counter-parts of these stars in the Gaia EDR3 catalogue. We then apply the [3]} parallax corrections to the stars as well as the
additional shift of \(\Delta \varpi = 0.007\)  mas found by VB21.
Using only stars which have published \(V\)  and \(I\)  band photometry by [2]}, a reddening \(E(B-V)<0.02\)  and Gaia EDR3 parallaxes with a relative precision \(\varpi /\epsilon _\varpi >20\) 
leaves us with a sample of 206 stars. Despite our more stringent limit on the parallax accuracy, our sample is almost a factor 10 larger than the one used by [1]}. Thanks to the superior accuracy
of the Gaia EDR3 parallaxes, our sample also contains about 20 stars with metallicities \(\mbox{[Fe/H]}<-2.0\) , while no accurate Hipparcos parallaxes were available for any of these stars. We finally use the SIMBAD astronomical
data base to exclude known binaries from this sample, leaving us with a sample of 185 stars.
